1. Field of the Invention
Embodiments of the present invention generally relate to an apparatus for performing multiple processes on a substrate in succession within an environmentally controlled atmosphere.
2. Description of the Related Art
Substrate throughput in semiconductor processing is always a challenge. If technology is to advance, semiconductor substrates continually need to be processed efficiently. Cluster tools have developed as an effective means for processing multiple substrates simultaneously without breaking vacuum. Instead of processing a single substrate and then exposing the substrate to atmosphere during transfer to another chamber, multiple process chambers can be connected to a common transfer chamber so that when a process is complete on the substrate in one process chamber, the substrate can be moved, while still under vacuum, to another process chamber that is coupled to the same transfer chamber.
Another benefit of cluster tools is that multiple substrates can be processed within the tool in different chambers at the same time. After one substrate has exited a process chamber and transferred into another process chamber, a second substrate can be placed into the first process chamber. Thus, sequential processes can be performed on different substrate simultaneously within the cluster tool.
To enter the transfer chamber, a substrate first passes through a load lock chamber. The load lock chamber may heat the substrate prior to processing. After all of the substrate processing to be performed within the cluster tool has completed on the substrate, the substrate is transferred back to the load lock where it can exit the cluster tool system.
Therefore, a cluster tool can be very useful in increasing substrate throughput. Of course, there is always a desire to increase substrate throughput even more. Thus, there is a need in the art to increase substrate throughput in an apparatus that performs multiple processes on a substrate in succession.